<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <!--
        <h1>--<h6>:
        <center>:居中显示，该标签在html5中已经不建议使用
        <input>:输入组键、该组件
    -->
    <center>
        <h1>百度</h1>
        <input type="text" size="32">
        <input type="button" value="百度一下">
        <!--    单选框和复选框可以用name属性将其属性划分为为1组，名字相同的为一组-->
        <input type="radio" name="gender">男
        <input type="radio" name="gender">女
        <br>
        <a href="http://www.jd.com">京东</a>

        <table  border="1">
            <tr>
                <td>1</td>
                <td>2</td>
                <td>3</td>
                <td>4</td>
                <td>5</td>
            </tr>
            <tr>
                <td rowspan="2" align="center">1</td>
                <td>2</td>
                <td colspan="2" align="center">3</td>
                <td>4</td>
            </tr>
            <tr>
                <td>2</td>
                <td>3</td>
                <td colspan="2" align="center">4</td>
            </tr>
        </table>
        
    </center>
    <h1>标题</h1>
    <h2>标题</h2>
    <h3>标题</h3>
    <h4>标题</h4>
    <h5>标题</h5>
    <h6>标题</h6>
</body>
</html>